You don't say what kind of music you're listening to, but if it has a lot of bass, the problem you're seeing is the stock speakers aren't set up for that.

I don't mean to say the speakers are bad (in fact, they're pretty good), just they are the wrong size to handle deep bass.

So, if you're cranking the volume to get bass, you're overwhelming the speakers and getting distortion.

If this is your situation, you're probably better off adding subwoofers and blocking the bass to the stock speakers, which btw is what I did. Once you keep the bass out of the stock setup, it can pump out a lot of mid and high range volume, and the new subwoofers will do the rest.

In my sig below, place your mouse over the "audio" section to see details of my setup.

Erwin 89 750iL Lowered (a little)

Mouse over for details >>> Engine/Driveline Wolf engine and throttle chips 19 lb, 4-hole (Design 3) fuel injectors Custom Intake based on 850csi parts Custom Cold Air Boxes Royal Purple 20W-50 3.64 LSD w/Royal Purple gear lube Royal Purple trans fluid Interior Phone removed, replaced with cut-to-length dash wood trim on hinge E38 Shifter Knob, Console Plate, and Boot M-Tech 2 M-technic Steering Wheel - air bag deleted E38 Self-Dimming Mirror Interior Light Fading Module (Shogun special) Audio BMW Business CD Player "CD43" Head Unit Refurbished factory amp w/equalizer Bass blockers (300hz/4ohm) on stock front kick panel speakers Rear deck speakers: Alpine SPS-13C2 5.25" 2 way 175 Watt with bass blockers Subwoofers: 2 JBL GTO804 8" 4-ohm subs Subwoofer install: custom sealed enclosure mounted behind ski bag opening Subwoofer amp: Alpine MRP-M450 400w MONO CD changer relocated to driver's door bottom pocket, actuated by bio- mechanical arm controlled by semi-intelligent nut behind the wheel Suspension H&R Lowering Springs (1/2 coil removed from fronts) Koni adjustable front shocks Stock rear shocks (self leveling) Racing Dynamics Stress Bar Stock front sway bar Dinan rear sway bar - 21mm M5 aluminum lower control arms Racing King rear subframe delrin inserts Front tires: 245-40-18 Goodyear Eagle F1 GS-D3 on 8.5" EuroTech rims Rear tires: 275-40-18 Michelin Pilot Sport PS1 on 9.5" EuroTech rims Exterior/Body 25% Side tint, 5% Rear tint BMW Mud flaps - rears trimmed to tire width Rear fender lips rolled Smoked side markers (after pic taken) Euro Smiley Headlights (after pic taken) Soft close trunk retrofit E66 trunk emblem "750 iL" (after pic taken) Zymol wax Way too many paint chips touched up Brakes Front Rotors: 850CSi, 324 X 30 mm, cross-drilled and slotted Rear Rotors: stock size, cross-drilled and slotted Pads: Hawk Performance Ceramic (may switch to HPS) Stainless steel lines Racing Blue brake fluid

• Stereo re-wiring (pic) - coldfrez 2008-09-05 13:01:48 (160 views)
  • HD Radio ($50 rebate before Sep 29th) (url) - Patrick C 88 750 160K 2008-09-08 23:10:08 (150 views)
    • Note that this rebate covers some 30 products - Patrick C 88 750 160K 2008-09-09 20:40:26 (32 views)
    • My HD radio installation just done today (pic) - Patrick C 88 750 160K 2008-09-09 20:39:24 (111 views)
      • Re: My HD radio installation just done today - cpseapeacp 2008-09-11 08:03:09 (32 views)
        • Thanks cp, mine is a rather inexpensive MP36 - Patrick C 88 750 160K 2008-09-11 17:18:10 (36 views)
      • Nice setup. One question.... - bcweir750 2008-09-09 23:31:03 (38 views)
        • I tested the VR3 unit commuting home last evening - Patrick C 88 750 160K 2008-09-10 16:52:12 (29 views)
  • What I did--long, but informative - cpseapeacp 2008-09-08 09:31:07 (61 views)
    • Thanks for the detailed description. Sounds like champ (nt) - Patrick C 88 750 160K 2008-09-08 23:02:19 (32 views)
  • Re: Stereo re-wiring - Hitmanx 2008-09-05 15:06:31 (50 views)
  • You don't have to re-wire...just get a 2 to 4 channel preamp adapter.. - oliverr871 2008-09-05 14:26:05 (66 views)
    • Look at the bottom, SNI-15/SNI-35 (link inside) (url) - oliverr871 2008-09-05 14:31:26 (51 views)
  • Diagram is standard amp wiring, but may not be enough - erwin 2008-09-05 13:43:09 (83 views)
    • I have a blaupunkt and exactly same prob as coldfrez - Patrick C 88 750 160K 2008-09-05 17:21:51 (40 views)
      • Re: I have a blaupunkt and exactly same prob as coldfrez - Isiah 90-735il 2008-09-06 23:21:27 (44 views)
        • noise filter, and 200 ohm resistors on -ve wires - Patrick C 88 750 160K 2008-09-08 22:56:59 (43 views)
          • Re: noise filter, and 200 ohm resistors on -ve wires - Isiah 90-735il 2008-09-10 21:10:08 (27 views)
            • This one (in URL link) is probably what I bought (url) - Patrick C 88 750 160K 2008-09-11 17:31:59 (28 views)
      • Not saying it's excessive by design - erwin 2008-09-05 18:28:10 (42 views)
    • Re: Diagram is standard amp wiring, but may not be enough (pic) - coldfrez 2008-09-05 13:52:51 (91 views)